Download Ramanathan et al, 2013 - University of California San Diego

Scripps Inst. of Oceanography
University of California at San Diego
Oakland, California, October 18, 2013
V. Ramanathan, University of California, San Diego, October 21,
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2013. ICAMP Inaugural Session
Los Angeles Civic Center masked by smog in 1948
SOURCE: Los Angeles Times photographic archive, UCLA Library
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California Environmental
Protection Agency
Air Resources Board
In 1967, California’s Legislature established
the California Air Resources Board (CARB).
CARB has worked with the public, the
business sector, and local governments to find
solutions to California’s air pollution problem.
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Air Pollution is a Major Killer
A New International Study was released this year
(Sponsored by WHO):
Lin et al, LANCET, 2013
Ambient particulate matter pollution accounted
for 3·1 million (2·7 million to 3·5 million)
premature deaths every year
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Premature mortality due to PM2.5.
NASA Earth Observatory, 2013.
Dark brown regions experience more than 1000 deaths per
1000 square kilometers.
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How Has California’s air quality Changed with time?
SCIENCE INFORMING POLICY
Three year, Multi-Institution study
http://www.arb.ca.gov/research/single-project.php?row_id=64841
LEAD INVESTIGATOR: V. Ramanathan
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University of California at San Diego
University of California at Berkeley
Lawrence Berkeley National Laboratory
Pacific Northwest National Laboratories
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Black Carbon (BC): Product of Incomplete Combustion
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The major component of PM from the Diesel Transportation Sector
About 75% of PM from Diesel Mobile sources is BC
The second largest contributor to global warming
Contributes directly to melting of snow packs, glaciers, and sea ice
Ramanathan et al, 2013: CARB 08-323
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Black Carbon Trends in California: Detection
Remote sites
Mostly Urban sites
Ramanathan et al, 2013: CARB 08-323
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Statewide BC Trends in California-Annual Mean
(Remote Sites)
Source: Bahadur et al, 2010
Ramanathan et al, 2013: CARB 08-323
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40 Years of Progress on Diesel Soot
Source: Kirchstetter et al. (2011)
Ramanathan et al, 2013: CARB 08-323
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Air pollution reduced 75-90% despite growth
Reproduced from: B. Croes, 2013 (CARB)
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Percent Change
1968-2008
200
150
100
50
0
-50
-100
Carbon
Monoxide
Nitrogen
Oxide
Vehicle
Sulfur Population Number
Dioxide
of Vehicles Miles
Ozone – Los Angeles peak cut over 70%, hours of exposure reduced 90%
PM10 – annual-average levels cut 75%
Air toxics – over 80% cancer risk reduction (since 1989)
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The important lesson to be learned is that cleaning
up the air does not necessarily deter development
The Co-Benefits are Huge
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Co-Benefit of Diesel Black Carbon Reduction To Climate
Change Mitigation
California’s CO2 emission (2009 ): 393 MMT/Yr
The reduction in diesel BC emissions from 1989 to
2008, is equivalent to reducing CO2 emissions by
21 (to 50) million metric tons annually
However, simultaneous mitigation of CO2 emissions from fossil
fuels is essential to limit global warming below 2oC.
Ramanathan et al, 2013: CARB 08-323
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Co-Benefits from Ozone precursor Reduction
Reduction in Ozone (smog):
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Should have reduced crop loss caused by high
Ozone concentrations
• Should have mitigated climate change since
Ozone is a powerful greenhouse gas
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Why Are We Assembled Here
• to examine how California achieved these
impressive gains in air pollution without
compromising development;
• Evaluate the nature and magnitude of scientific,
technological and organizational infrastructure
and policy initiatives that are required for India
to make similar progress in the coming decades.
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India’s transportation sector is experiencing impressive
growth. The number of vehicles has grown from about
20 million in 1991 to about 140 million in 2011.
Air pollution has become a major problem. WHO estimates
700,000 deaths each year attributed to air pollution.
In cities like Bangalore the transportation sector
contributes more than 50% to PM2.5 (as of 2011),
nearly the same as in California.
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November 14 2006
December 21 2001
What would it take to accomplish similar improvements in air quality
of mega cities such as Mumbai, Bangalore, Delhi, Kolkatta and
Chennai within the next 30 years, without impeding the economic
development of India?
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Climate Action Team Report
Finally, promoting action regionally and internationally that
reduces climate change risks and expands clean energy
industries and green jobs is a high priority.
My Personal Commentary
California’s successful policies for reducing BC
based on targeted Science should serve as a
Knowledge to Action example for the World
If California’s black carbon reduction from diesel
can be replicated globally, the projected global
warming for the coming decades can be mitigated by
about 10 to15 percent*, slow down glacier melt and
sea ice retreat in addition to protecting lives and
crops.
*based on estimates using the Ramanathan and Xu, PNAS, 2010 study
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